1. Field of the Invention
The present invention relates to compositions containing bisulphite adducts of (poly)isocyanates or (poly)isothiocyanates (the poly-cyanates hereinafter being abbreviated to BAPs), with improved properties.
A BAP is defined as a compound containing two or more radicals drawn from type (I) and/or type (II) groups ##STR1## where X.sup.+ is a cationic group with one or more positive charges to maintain electrical neutrality; for example, sodium, potassium or ammonium.
Similarly, adducts of the mono-isocyanates or monoisothiocyanates contain only one radical, drawn from (I) and/or (II). The BAPs, however, are preferred.
2. Description of the Prior Art
In copending U.S. Ser. No. 330,404 (Australian Application No. 52,234/73), methods were described for the preparation of BAPs by the reaction of polyisocyanates with aqueous solutions containing bisulphite salts and water-miscible organic solvents. Such compositions on prolonged storage (one year or more) at room temperature undergo slow decomposition, and this process was found to be hastened by heating.